Traffic chaos after bridge the size of a football field COLLAPSES onto the main freeway from Los..

UK Daily Mail ^ | May 6, 2014 | James Gordon

[C19fan]

For almost a year and a half workers had been constructing a bridge to cross the main Interstate that runs between Los Angeles and Las Vegas, but it took just minutes to bring the entire structure crashing to the ground. The blaze began after a construction workers' blowtorch was fanned by strong winds and ignited the wooden scaffolding that was being used to build the new flyover, across Interstate 15 in Herperia, California. Driven by high winds, the fire took hold extremely quickly and began burning the supports surrounding the bridge. Debris began to fell onto the I-15 minutes after the fire began, the road was eventually closed to traffic at 1:30pm yesterday as the $32 million construction project slowly turned into a pile of ash and twisted metal.

[GeronL]

Did they use Chinese and illegal Mexican labor?

[lacrew]

Classic. A blacksmith is actually a very good way of explaining how metal can be weakened, without being “melted”.

[Zathras]

I thought the same thing. Precast would have been faster.
Sounds like the forms were fully oiled getting ready for concrete.

[zeestephen]

Thanks - excellent summary.

It looks a lot like the way we pour “quake proof” floors in multi-story buildings in Seattle, except about ten times thicker in the bridge.

[thecodont]

The fire in Boston last month that killed 2 firefighters was caused by welders who didn't pull a permit and fled after the fire started.

Likely illegal aliens, and likely an illegal alien in this story also. Poorly trained, barely literate, not certified, not here legally, hired on a streetcorner, paid under the table, and ready to flee at the first sign of trouble, like a hit-and-run driver.

[PA Engineer]

It’s too arid out there to use wood scaffolding. You need to use metal scaffolds...unless it isn’t your money building it.M

I wonder if it was formwork. That follows to why they were not using thermit welds on the rebar.

[tpmintx]

Here in California, we have big ass earthquakes,

Do you recall the Loma Prieta earthquake? I was in a high-rise in Santa Clara for that one. I know all about earthquakes.

Yes, there are earthquakes. That said, build the precast beams bigger and with lots more re-bar. You still don't need to cast them in place. You do need to build and cast hugely strong supports in place, but these are not generally in traffic lanes.